1. Field of the Invention
This invention relates to an array lens and its applications.
2. Description of the Prior Art
It is well known to form an array lens by arranging a plurality of refractive index gradient type lenses or by arranging a plurality of bar lenses. However, such an array lens has disadvantages that during the manufacture thereof, it is difficult to arrange lens elements and that the manufacturing cost thereof is high. Further, it is difficult to vary the imaging magnification of such an array lens.
Also, as a variable focus lens, there have heretofore been proposed one as disclosed in Japanese Laid-open Patent Application No. 36857/1980 wherein a container of elastic material is filled with liquid and the shape of the container is varied by the pressure of the liquid, and one which uses piezo-electric elements as disclosed in Japanese Laid-open Patent Application Nos. 110403/1981 and 85415/1983. However, the former so-called liquid lens requires a liquid reservoir and a pressing device and this leads to a problem in making the element compact, and the latter has a disadvantage that the amount of variation thereof cannot be secured very greatly.